Most of what you say would seem to be best answered by Paul.
From my perspective, it's simply a case of- now that we have a planning sub-forum let's use it. If we don't, it will only further complicate the placement of planning-related posts.
I can understand some of your points, though I suspect we use a different front page to access the site. I start with http://www.archiseek.com
, which shows a list of all threads that contain new posts, so this double visit business you speak of isn't an issue for me. It also means I can see the posts in the World, UK, Suggestions etc. threads at a glance.
If Paul wanted to re-amalgamate them I guess I'd have no problem, but I appreciated the change and wanted to give it a chance (with a little gentle encouragement).